package com.itheima.execption;

import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerExceptionResolver;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

// 自定义异常
// @Component
public class ExceptionResolver implements HandlerExceptionResolver {
    @Override
    public ModelAndView resolveException(HttpServletRequest httpServletRequest,
                                         HttpServletResponse httpServletResponse,
                                         Object o,
                                         Exception ex) {
        System.out.println("my exception is running.....");

        ModelAndView modelAndView  = new ModelAndView();

        // 空指针处理
        if (ex instanceof NullPointerException){
            modelAndView.addObject("msg","空指针异常！");
        }else if (ex instanceof ArithmeticException){
            modelAndView.addObject("msg","算术运算异常！");
        }else{
            modelAndView.addObject("msg","未知异常！");
        }




        modelAndView.setViewName("error.jsp");

        return modelAndView;
    }
}
